Drones-caught sea urchins being used to clean salmon cages

Jens Kristian Henriksen, CEO of the Norway-based company Ecofang, will use a mini-boat and a drone to catch sea urchins. These are to be used, among other things, for cleaning cages, which can potentially reduce costs to salmon farmers.

Sea urchins are natural scavangers and can be placed both on the outside and on the cages, to clean the net and seabed for overgrowth, dead fish and other sediments, writes forskning.no.

“Today, the aquaculture industry spends about NOK 1 billion* cleaning cages. They have to hoist them up with a crane and flush the dirt, or lower an ROV that can clean them while they are in the sea,” said Henriksen, who thinks sea urchins can help to balance biology and marine environment around the fish farms.

Green gold? The Strongylocentrotus droebachiensis is commonly known as the green sea urchin PHOTO Wikipedia

To catch the sea urchins, Ecofang and Henriksen will adopt a method that to make the process quite easy. This is done by using a mini submarine (ROV) which is transported to the catching areas with a drone. When the baskets are full of urchins, the drone will fly to land where the bottom of the baskets open, and the sea urchins are released into a seawater tanker on land.

According to Henriksen, the drone will be able to carry ten loads a day, with a catch of up to 30 kilos per flight. The number of green sea urchins ready to be harvested in Norway is estimated to be 80 billion pieces or around 56 thousand tonnes of the spiny creatures.

“The drone means that we do not have to put our legs in a boat or on unsafe grounds, and avoid the risky diving. The cost and risk of diving is the main reason why we do not have a sea urchin nutrition in Norway. With drones, two people on land can operate the catch,” he said.

In the newspaper Framtid i Nord, Henriksen said that the company is dependent on investors to be able to get started with the project.